Olefin based polymers such as polyethylene and/or polypropylene are produced via various catalyst systems. Selection of such catalyst systems used in the polymerization process of the olefin based polymers is an important factor contributing to the characteristics and properties of such olefin based polymers.
Polyethylene is known for use in the manufacture of a wide variety of articles. The polyethylene polymerization process can be varied in a number of respects to produce a wide variety of resultant polyethylene resins having different physical properties that render the various resins suitable for use in different applications. It is generally known that polyethylene can be produced in one or more conventional reactors e.g. loop reactors, spherical reactors, isothermal reactors, fluidized bed gas phase reactors, stirred tank reactors, batch reactors, in parallel, series, and/or any combinations thereof. In solution phase reactors, the ethylene monomers and optionally one or more comonomers and catalyst system are present in a liquid diluent, such as an alkane or isoalkane, for example isobutane.
Despite the research efforts in developing catalyst systems suitable for polyolefin, such as polyethylene and/or polypropylene polymerization, there is still a need for a pro-catalyst and a catalyst system exhibiting an improved α-olefin response (i.e. lower reactivity ratio).